Process for dyeing skins, hairs, and the like



Patented July 3, 1923. i

UNITED STATES PATENT omen.

J osm RALTWABSER AND LEQPOLD KIRBEBGEB, F BERLIN AND BERLIN-GRAB- LOTTENBUBG, GERMANY, ASSIGNOBS .TO AGTIEN GEBELLBCHAFT FUR ANILIN I'ADBIKA'IION, OF BERLIN, GERMANY.

PROCESS FOR DYEING SKINS, HAIBS, AND THE LIKE.

llo Drawing. Applicatlon flled January 25, 1922. Seriaifl o. 581,778.

To all wkomz't may concern: chromium mordants are brownish grav,f80

Be it known that we, Osm KALTWASSER those on skins prepared with copper morand LnoronnKmnnnenn, citizens of the Gerdan-ts are greenish gray; on skins pre man Republic residing at Berlin, Germany, with iron mordants a gray is produce and Berlin-Charlottenbur'g, German our By d ein in an alkaline solution, for ex- P. 0. address bei Urbanstr. 178, erlin, ample y a dition of 2 grams of ammonia 35 Germany, and Schi lerstr. 121, Berlin, Ger- (of 25% strength) .to the above dyeing bath many, have invented certain new and useful dyeings which are more yellowish result.-

Improvements in Processes for Dyeing Having now described our invention and 1 Skins, Hairs, and the like, of which the folthe manner in which it may be performed lowing is a ification. what we claim is, a

Our invention relates to a new process for 1. The herein-described process for dyedyeing skins, hairsand the like and consists ing furs, feathers, hairs and the like matein ash with a solution of 2.7 -d'ioxynaphrial, eonsistingin acting on the material to p thalene 1n the presence of an oxidizing agent be dyed with a solution of 2.7-diox a hupon mordanted or non-mordanted material. thalene in the presence of an oxidizing (a The tints thus obtained are generally agent. speaking gray inclining to green of a very .2. .The herein-described rocess for dyegood fastness. ing furs, feathers and the 1i 0 material, con- The following example illustrates our insisting in acting on the mordanted material vention without limiting it; with a solution of 2.7-dioxynaphthalene in '50 The well-washed skin is handled for some the-presence of an oxidizing 11 nt. hours at ordinary temperature in a bath In testimony whereof we a our signa-' which contains r liter2 grams 2.7-dioxytunes in presence of two witnesses; v

na hthalene ami f 0 grams of hydrogen per- OSKAR KALTWASSER.

oxide (about 3% strength). The skin is i LEOPOLD KIRBERGER. then well washed. and ished as usual, a Witnesses: gra "shade being obtained. v C. Ho nznnmamr,

'Ehetints obtained on skins prepared with. Cmmns L. 

